- Plant Kingdom.
- Subkingdom, Spermatophyta.
- Group (not used in a definite sense).
- Class, Gymnospermæ.
- Order, Pinales.
- Family, Pinaceæ.
- Genus, Pinus.
- Species, strobus, or, in full,
- Pinus strobus, the white pine.
Group Angiospermæ.
I. CLASS MONOCOTYLEDONES.
941. Order Pandanales.—Aquatic or marsh plants. The cattail flags (Typha) and the bur-reeds (Sparganium), each representing a family. The name of the order is taken from the tropical genus Pandanus (the screw-pine often grown in greenhouses).
942. Order Naiadales.—Aquatic or marsh herbs. Three families are mentioned here.
The pondweed family (Naiadaceæ), named after one genus, Naias. The largest genus is Potamogeton, the species of which are known as pondweeds. Ruppia occidentalis occurs in saline ponds in Nebraska, and R. maritima along the seacoast and in saline districts in the interior.
The water-plantain family (Alismaceæ) includes the water-plantain (Alisma) and the arrow-leaves (Sagittaria).
The tape-grass family (Vallisneriaceæ) includes the tape-grass, or eel-grass (the curious Vallisneria spiralis).
943. Order Graminales.—Two families.
The grass family (Gramineæ), the grasses and grains.